Center for Industrial and Medical Ultrasound, Applied Physics Lab, University of Washington, 1013 North East 40th Street, Seattle, Washington 98105-6698, USA.
J Acoust Soc Am. 2011 Feb;129(2):622-32. doi: 10.1121/1.3531809.
Measurements of the wind noise measured at the ground surface outdoors are analyzed using the mirror flow model of anisotropic turbulence by Kraichnan [J. Acoust. Soc. Am. 28(3), 378-390 (1956)]. Predictions of the resulting behavior of the turbulence spectrum with height are developed, as well as predictions of the turbulence-shear interaction pressure at the surface for different wind velocity profiles and microphone mounting geometries are developed. The theoretical results of the behavior of the velocity spectra with height are compared to measurements to demonstrate the applicability of the mirror flow model to outdoor turbulence. The use of a logarithmic wind velocity profile for analysis is tested using meteorological models for wind velocity profiles under different stability conditions. Next, calculations of the turbulence-shear interaction pressure are compared to flush microphone measurements at the surface and microphone measurements with a foam covering flush with the surface. The measurements underneath the thin layers of foam agree closely with the predictions, indicating that the turbulence-shear interaction pressure is the dominant source of wind noise at the surface. The flush microphones measurements are intermittently larger than the predictions which may indicate other contributions not accounted for by the turbulence-shear interaction pressure.
利用 Kraichnan [J. Acoust. Soc. Am. 28(3), 378-390 (1956)] 的各向异性湍流镜像流模型，对户外地面测量的风噪声进行了分析。开发了预测湍流谱随高度变化的行为的方法，以及针对不同风速剖面和传声器安装几何形状，在表面处的湍流剪切相互作用压力的预测方法。将理论上的速度谱随高度变化的行为与测量结果进行了比较，以证明镜像流模型适用于户外湍流。使用气象模型测试了对数风速剖面在不同稳定条件下的分析适用性。接下来，将湍流剪切相互作用压力的计算结果与表面平齐的传声器测量值和与表面平齐的泡沫覆盖的传声器测量值进行了比较。在薄泡沫层下的测量值与预测值非常吻合，表明表面处的风噪声主要来源于湍流剪切相互作用压力。表面平齐的传声器测量值偶尔会大于预测值，这可能表明还有其他未被湍流剪切相互作用压力考虑在内的因素。
